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See detailContribution à la compréhension de l'immunopathogénie de l'aspergillose nasosinusale chez le chien
Vanherberghen, Morgane ULg

Doctoral thesis (2014)

Sinonasal aspergillosis is a sever fungal rhinosinusitis mainly affecting large breed dogs in their mid ages. Its most common causal agent is A. fumigatus, a fungus that is largely spread in the ... [more ▼]

Sinonasal aspergillosis is a sever fungal rhinosinusitis mainly affecting large breed dogs in their mid ages. Its most common causal agent is A. fumigatus, a fungus that is largely spread in the atmosphere. As of today, the diagnostic and treatment for this disease remain a challenge for the practicing veterinary doctor. Very little data is available to explain why such a ubiquitous fungus induces a sever rhinosinusitis in otherwise healthy dogs, while other dogs do not present any sign of fungal infection. The authors of a study analysing the expression of mRNA encoding for certain cytokines and chimiokines in the nasal mucosa of SNA affected dogs, propose the assumption that dogs develop a protective immunity (Th1) against A. fumigatus, but that it could be blocked by an excessively intense regulating immunity (massive production of IL-10). Indeed, it is commonly described that in humans affected by invasive aspergillosis, as well as in mice-based models, the production of immunoregulating cytokines (IL-10) should be considered as a sign of the escalation of the sickness and an absence of its remission. The objective of this thesis was to investigate the adaptive immunity reaction of SNA affected dogs based on the assumption that sick subjects develop a protective immunity that is antagonised by a disproportional regulating immunity. Three axes of analysis have been considered to answer this objective. The first looked into the difference of expression and/or production of cytokines and transcriptor factors prototypics of the different adaptative and regulatory immunological paths: Th1 (IFN-γ and Tbet) – Th2 (IL-4 and GATA3) – Th17 (IL-17A and RORc) and Treg (IL-10 and FoxP3) in PBMC of affected and healthy dogs after A. fumigatus stimulation. Secondly, an analysis of genes by microarray has been carried on nasal mucosa biopsies of affected and healthy dogs. Thirdly, the promotor zone of the gene encoding IL-10 in dogs has been analysed by sequencing. This study has been done within three cohortes of dogs: Rottweiler-Labrador and Golden containing affected and healthy dogs. The objective was to investigate, as it is the case in human medicine, the possibility of a genetic modification as a factor susceptible of leading to SNA development. The results of the first study revealed that: (1) the PBMC of half the controls dogs and every affected dogs expressed a relevant overexpression of IFN-γ. This increase was significantly more important within PBMC of affected dogs. The analysis of IFN-γ production in culture supernatants was in accordance with these last observations. A significant increase in the expression of mRNA coding for Tbet was also observed in half of the PBMC of affected dogs. (2) a significant increase in expression of mRNA encoding IL-4 was observed in the PBMC of most of the affected and healthy dogs. This increase was significantly higher in the PBMC of affected dogs than in the healthy dogs. (3) the PBMC of most control and affected dogs also revealed an increase in expression of mRNA encoding IL-17A. This increase was statistically more important in the PBMC of affected dogs than in the healthy dogs. (4) a relevant decrease in mRNA expression encoding IL-10 was observed in the PBMC of more than half of the affected dogs. The expression of the mRNA encoding IL-10 was significantly smaller in the PBMC of affected dogs than in the healthy dogs. The microarray analysis showed that: (1) amongst the 49 overexpressed biological groups, 13 were associated to the immunological or inflammatory process; (2) the nasal mucosa of affected dogs presented an increase in the expression of genes encoding for molecules involved directly (IFN-γ and STAT4) and indirectly (IL-16, CCL3, CCL4, and CXCL10) in the development of protective Th1 immunity, as well as molecules involved in the regulatory branch of the immune response (IL-16 and Ikaros). The sequencing analysis of the promotor region of the gene encoding IL-10 revealed the presence of polymorphisms. Three polymorphisms were observed more frequently in clones belonging to the three studied cohorts, excepted for the clones belonging to SNA affected Rottweiler. The polymorphisms observed in dogs were not similar to those described in humans. The first study showed an increase in the expression of mRNa encoding IFN-γ - Tbet – IL-4 and IL-17A in most of the PBMC of the affected dogs, and a decrease in the expression of IL-10 in comparison with the PBMC of healthy dogs. Similar results were observed in mice repeatedly affected by A. fumigatus. The suggested hypothesis was that an intense Th17 immunity resulted in a massive inflammatory reaction leading to a favourable environment were A. fumigatus was able to proliferate as hyphae. In return, hyphae would lead to the development of a non-protective Th2 immunity. It is tempting to suggest that the same hypothesis could be made for dogs affected by SNA. In order to reinforce this hypothesis, we should compare the expression of the different molecules involved in the Th17 immunity inside the nasal mucosa of affected and healthy dogs. Additionally, we should be running a kinetic study based on the expression of prototypical cytokines in parallel with the analysis of the production of these cytokines in culture supernatants. Ideally these studies should use DC and lymphocytes isolated from the nasal mucosa of affected and healthy dogs. In conclusion, an new hypothesis could be formulated: the possibility that not the overstimulation of the regulatory branch of the immunity response but an overstimulation of the Th17 branch of the immune response could be the cornerstone of the incapacity of dogs to clear from their SNA. The results of the microarray study were partially in accordance to the starting hypothesis. Indeed, the results showed an overexpression of genes involved in in the development of the protective Th1 (IFN-γ, STAT4, IL-16, CCL3, CCL4, and CXCL10) as well as genes involved in the regulatory path of the adaptive immunity (IL-16 and Ikaros). But the results of this study did not show an increase in IL-10. No conclusion could be drawn from these results; indeed, they were only the reflection of a fixed image at a given moment and we cannot consider qPCR results as the exact replica of the production of cytokines in the microenvironment. Nevertheless this study pointed out new possible areas of research. The results obtained after the sequencing of the promotor zone of the gene encoding IL-10 did not show any clear difference between affected and healthy dogs. However, this study was undertaken with a very limited number of dogs. In order to further assess the possibility of a genetic modification as the cornerstone of the development of SNA, more dogs should be analysed and the sequencing analysis should be run in parallel with an ELISA analysis. [less ▲]

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See detailContribution à la compréhension du fonctionnement hydrogeologique du système aquifère dans le bassin du Kou (Burkina Faso)
Sauret, Elie ULg

Master of advanced studies dissertation (2008)

Located at the South of the town of Dioulasso sore, economic capital of Burkina Faso, the basin of the Kou consists of sandy, carbonated and clayed formations dated from the Precambrian one. These ... [more ▼]

Located at the South of the town of Dioulasso sore, economic capital of Burkina Faso, the basin of the Kou consists of sandy, carbonated and clayed formations dated from the Precambrian one. These formations constitute materials of four aquifers formations whose geometrical characteristics and the interactions with the rivers and the important sources of Nasso (10.000 m3/h) and Pésso (600 m3/h) remain complex and badly known. In order to provide a better comprehension of the hydrogeology of this vast basin of 1860 km2, the present study was initiated. For the needs for the study, the limits of the Kou basin were extended to its natural borders: the Mouhoun river in North-Western and the cliff of Banfora in the South-East. The four aquifers formations considered as a single hydrogeological unit, were modelled considering steady state groundwater flow conditions. Modeling made it possible to understand the interactions groundwater -water of surface by quantifying exchanged water flows. The results provided by this model appear acceptable in comparison of the allowed assumptions, and the data we have used. [less ▲]

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See detailContribution à la connaissance de l’ichtyofaune de l’Inkisi au Bas-Congo (RD du Congo)
Wamuini Lunkayilakio, Soleil; Vreven, Emmanuel; Vandewalle, Pierre ULg et al

in Cybium (2010), 34(1), 83-91

L’étude de la composition et de la distribution de la faune ichtyologique de la partie congolaise de la rivière Inkisi a permis d’inventorier 61 espèces réparties en 37 genres appartenant à 15 familles ... [more ▼]

L’étude de la composition et de la distribution de la faune ichtyologique de la partie congolaise de la rivière Inkisi a permis d’inventorier 61 espèces réparties en 37 genres appartenant à 15 familles. Les Cyprinidae sont les mieux représentés avec 15 espèces. Les Mormyridae, Cichlidae et Clariidae viennent ensuite avec respectivement 11, 9 et 7 espèces. La composition spécifique des communautés des poissons est différente, du cours supérieur vers l’aval. Le profil longitudinal de cette partie de l’Inkisi est caractérisé par la présence de trois chutes qui sont, de l’aval vers l’amont : la chute de Mantumpu (8 m de hauteur) à l’entrée de l’Inkisi dans le fleuve Congo, la chute de Zongo (58 m) à 6 km du confluent et la chute de Sanga (24 m) à 10 km de la chute de Zongo. La présence de ces chutes sur le cours de la rivière semble avoir influencé l’ichtyofaune et pourrait même être à l’origine du nombre important d’espèces endémiques en amont. Si l’on s’en tient au cours principal, la différence entre la richesse spécifique en amont et celle en aval n’est pas significative, probablement à cause de la morphologie du bassin. La richesse et la composition spécifique de la partie comprise entre les deux chutes (Zongo et Sanga) ne diffèrent pas de celles de l’amont de la chute de Sanga. Toutefois, cette composition est fort différente de celle de la zone tout en aval. [less ▲]

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See detailContribution à la connaissance des Chrysopidae de Belgique : bilan des captures réalisées à Gembloux.
Mignon, Jacques ULg; Bozsik, Andras; Gaspar, Charles

in Notes Fauniques de Gembloux (2000), 41

Douze espèces de Chrysopidae furent identifiées: H. elegans, N. flava, N. pallida, Ch. ciliata, Ch. perla, Ch. pallens, D. flavifrons, D. prasina, D. ventralis, T. gracilis, Ch. carnea et C. albolineata ... [more ▼]

Douze espèces de Chrysopidae furent identifiées: H. elegans, N. flava, N. pallida, Ch. ciliata, Ch. perla, Ch. pallens, D. flavifrons, D. prasina, D. ventralis, T. gracilis, Ch. carnea et C. albolineata. Une espèce, Tjederina ventralis est nouvelle pour la faune belge. [less ▲]

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See detailContribution à la conservation de la flore cupro-cobalticole endémique du Katanga (R.D.C.) : Conservation en banque de graines et régénération d'espèces métallicoles
Boisson, Sylvain ULg

Master's dissertation (2011)

Metallophytes are plants that represent the biodiversity of metal-rich soils. Some of them are able to accumulate high metal concentrations: metal hyperaccumulators plants. In Katanga (RD Congo), 32 ... [more ▼]

Metallophytes are plants that represent the biodiversity of metal-rich soils. Some of them are able to accumulate high metal concentrations: metal hyperaccumulators plants. In Katanga (RD Congo), 32 species have been identified as copper-cobalt endemic but mining activities are still a threat to outcrop ecosystems. We must characterize native environmental parameters (realized niche) and the full range of environmental conditions in culture (fundamental niche) to conserve, preserve and restore these ecosystems. Six representative species of the natural copper gradient were selected after soil-species data analyses (Crepidorhopalon perennis, Crotalaria cobalticola, Gladiolus ledoctei, Haumaniastrum robertii, Lopholaena deltombei and Sopubia mannii). The study determined their behavior (germination, survival) and their development (vegetative measures) on one group of natural soil (from three copper gradients of Fungurume V hill), two groups of artificially contaminated soils with incremental doses (copper sulfate and copper hydroxycarbonate: 500, 2000 and 5000 mg.kg-1) and one uncontaminated soil (control) by two types of plant establishment (direct seeding and transplant from Petri dishes). The results depend on species habitat and show that four of these species can grow on uncontaminated soil in the early stages of growth. In addition, the seed bank (in Faculty of Agronomy - University of Lubumbashi) management (cleaning, updating and germination tests of accessions) was maintained using standard methods. The results of germination tests demonstrated the effectiveness of some conservation methods and helped to provide recommendations for the methodology. [less ▲]

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See detailContribution à la désinfection de l'eau par photosensibilisation avec des extraits de plantes
Sunda Makuba, Teddy ULg

Doctoral thesis (2012)

La problématique de l’accès à l’eau par les populations des pays en développement constitue toujours de nos jours un défi important à relever pour contribuer à un développement durable tout en ... [more ▼]

La problématique de l’accès à l’eau par les populations des pays en développement constitue toujours de nos jours un défi important à relever pour contribuer à un développement durable tout en garantissant des conditions sanitaires satisfaisantes. Malgré les Objectifs du Millénaire pour le Développement (OMD), de nombreux pays souffrent encore actuellement d’un manque d’accès à l’eau. En République Démocratique du Congo, seuls 26% de la population a accès à l’eau. Au-delà de la satisfaction des besoins humains assurés par la fourniture de la quantité d’eau nécessaire, il s’agit aussi de veiller à garantir sa bonne qualité, particulièrement la qualité microbiologique. Parmi les divers procédés de désinfection de l’eau au niveau familial, la présente contribution a pour objectif l’amélioration de la méthode de désinfection solaire par application du processus de photosensibilisation. En présence de lumière, un photosensibilisateur génère dans l’eau l’oxygène singulet très réactif conduisant à la destruction des microorganismes. Certaines plantes utilisées dans la pharmacopée traditionnelle pour soigner les infections microbiennes et parasitaires sont capables d’initier cette réaction de photosensibilisation. Dans un premier temps, parmi une dizaine de plantes analysées, nous avons mis en évidence l’activité photosensibilisante d’extraits non alcaloïdiques de Cassia alata, Cassia occidentalis, Carica papaya, Phyllanthus niruri et Coleus kilimandschari. L’inactivation des coliformes fécaux a été remarquée après trois heures d’ensoleillement, celle-ci se manifestant après une heure d’exposition lorsque le milieu est saturé en oxygène. Tout en étant libéré de la contrainte liée à la saturation du milieu en oxygène, l’étude des huiles essentielles extraites de plantes de la famille des Rutacées a montré une inhibition complète des coliformes fécaux présents dans l’eau après deux heures d’ensoleillement pour Citrus reticulata et Citrus limonum et une heure d’ensoleillement pour Citrus bergamia. L’examen de cette dernière huile en spectrométrie de masse a mis en évidence la présence de méthoxy-5 psoralène (MOP-5), responsable de l’activité photosensibilisatrice. Utilisé en solution dans l’eau, le MOP-5 a confirmé son rôle de photosensibilisateur et son efficacité désinfectante avec un abattement de 4 unités logarithmiques pour les Coliformes fécaux après une heure d’exposition et de 3 unités logarithmiques pour les Entérocoques fécaux après seulement 5 minutes d’exposition. La fixation du MOP-5 sur un support solide a permis de récupérer le photosensibilisateur après usage tout en conservant son pouvoir désinfectant supérieur à la forme libre. Le dispositif MOP-5/polystyrène a permis d’observer une inhibition complète des Coliformes fécaux après seulement 6 minutes d’exposition et deux minutes pour les Entérocoques fécaux. Cette recherche constitue un premier travail exploratoire qui ouvre la voie vers un nouveau processus de désinfection de l’eau par photosensibilisation à partir d’extraits de plantes. Mais il conviendra de préciser les modalités pratiques d’application afin de rendre ce processus opérationnel. [less ▲]

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See detailContribution à la détermination d’impacts économiques de la fertilisation d’un ferralsol par l’extrait aqueux de cendres de Cynodon dactylon à Kisangani, R.D.Congo
Bolakonga Ilye, Antoine Bily ULg; Moango Manga, Adrien; Natdanga Lele et al

in Annales de l’Institut Facultaire des Sciences Agronomiques de Yangambi (2007), 1

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See detailContribution à la détermination du profil en COVs des effluents gazeux de séchage industriel de levain
Eloundou Mballa, Pierre Patrick ULg; Fauconnier, Marie-Laure ULg

Poster (2013, July 02)

During the industrial drying of sourdough, there is an evaporation of a part of the volatile compounds and those generated during the process. These compounds are evacuated with waste and lost for the ... [more ▼]

During the industrial drying of sourdough, there is an evaporation of a part of the volatile compounds and those generated during the process. These compounds are evacuated with waste and lost for the industry. A complete characterization of the aromatic profile would open ways towards a co-valuation of some of these COVS. [less ▲]

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See detailContribution à la gestion intégrée des eaux et des sols à travers l'application du contrat de rivière Sourou au Burkina Faso
Rosillon, Françis ULg; Bado-Sama, H.

in La GIRE décryptée, éléments de renforcement de la GIRE en Haïti etdans les PED (2010)

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See detailContribution à la gestion intégrée des eaux et des sols à travers l'application du contrat de rivière Sourou au Burkina Faso.
Rosillon, Françis ULg

Conference (2007, November)

Inspired from the experience of river contract in Wallonia (Belgium), the implementation of a first river contract has been initiated in a West-African country, Burkina Faso, since 2003. In the program of ... [more ▼]

Inspired from the experience of river contract in Wallonia (Belgium), the implementation of a first river contract has been initiated in a West-African country, Burkina Faso, since 2003. In the program of actions approved by the river committees in December 2005, the protection of water resources and grounds was taken into account. The first realized actions contributed to slow down the degradation of the ecosystems by recreating a space buffer between the river and the cultivated zones. A first project of restoration of the gallery forest alongside the stream was implemented to fight against desertification. This project arouses a strong mobilization of the local actors and demonstrates that such a contractual tool of participative management can make an interesting contribution in favour of an integrated management of waters and grounds. In a river contract, these two resources are associated in a common reflection which transcends still too often sector-based policies. [less ▲]

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See detailContribution à la maîtrise des contaminations des plantes potagères par les éléments traces métalliques
Liénard, Amandine ULg

Master's dissertation (2009)

The set of problems resulting from metallic trace elements in vegetable gardens is increasingly in the heart of the question, evidently as much as a concern for public health than in terms of sustainable ... [more ▼]

The set of problems resulting from metallic trace elements in vegetable gardens is increasingly in the heart of the question, evidently as much as a concern for public health than in terms of sustainable environmental management. Throughout this work, I aimed at studying particular aspects of metallic trace contaminations, mainly their dispersal across the soil and soil-plant transfers. Firstly, a toposequential study focused on the source of contamination was performed in order to allow the description of the relation between the distance from the source of contamination and the distribution of the metallic trace elements. It was observed that as far the distance from the source of contaminations is as low the concentrations of traces elements are. Secondly, two distinct experiments were performed to assess the soil-plant transfers. The first one consisted in a culture on a range of contaminated soils of two vegetables varieties (i.e. lettuce and endive). As a result, it was shown that the two varieties accumulated similarly the trace elements. The aim of the second experiment was to study the relationship of different organic matters on the phytoavailability of the traces elements. It was performed by culturing Spinacia oleracea on three contaminated soils where three different organic amendments (manure cow, manure cow-hen-horse, and compost) were added with four different concentrations. Results based on soils and S. oleracea metallic trace elements concentrations were compared to standards in application for the contaminations in trace elements in the soils and to the foodstuff standards fixing the concentrations limits of cadmium and lead in the vegetable-leafs. Finally, it was observed that it was the “manure of cow” amendment used at a rate of 120g/kg of soil that represented best way to avoid large transfers of metallic trace elements into the different parts of the plant susceptible to be eaten. [less ▲]

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See detailContribution à la mise au point d'un dispositif de culture associée cotonnier-niébé dans la région de Gandajika au Zaïre
Delhove, G.; Mergeai, Guy ULg; Mulamba, K.

in Mémoires de la Société Royale d'Entomologie de Belgique (1992), (35), 375-378

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See detailContribution à la mise au point d'une méthode de lutte biologique contre la maladie des pourritures de la couronne de la banane
Lassois, Ludivine ULg

Master's dissertation (2003)

The antagonist activity of two yeast strains (Pichia anomala K strain and Candida oleophila O strain) against the parasitic complex responsible for crowns rot of banana has been evaluated. Their ... [more ▼]

The antagonist activity of two yeast strains (Pichia anomala K strain and Candida oleophila O strain) against the parasitic complex responsible for crowns rot of banana has been evaluated. Their efficiency has been tested on three separated fungi : Colletotrichum musae, Fusarium moiliforme, Cephalosporium sp. and on a parasitic complex formed by the association of these three fungi. Antagonist effects have been observed both on the two first fungi and on the complex. Strain O added at 108 ufc/ml on crowns which were previously inoculated with the complex showed the highest protection (56,0 %). This protection was superior to those observed against the fungi inoculated separately. The influence of the time between the addition of the O strain (108 ufc/ml) and the inoculation of the pathogens on the level of protection has also been measured. It appeared that protection by the O strain was remarkably reinforced when the strain was added 24 hours before the complex (57,0 %). This, in comparison with the additions performed 15 minutes or 3 hours after the pathogens inoculation. The utilisation of the O strain at 108 ufc/ml has been combined with the utilisation of 50μm polybags. These latter allow the formation of a modified atmosphere during the length of the bunches transfer. The protection level was at 61,0% when both methods were combined whereas protection by the yeast alone was of 41,0%. A strict correlation between the severity of the symptoms and the protection by the yeast has been highlighted. When the severity of the disease increases, protection by the yeast decreases. [less ▲]

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